Leishmaniasis

Leishmaniasis (leesh-muh-NYE-uh-sis) is a parasitic infection spread by
sand flies. It causes symptoms ranging from sores on the skin to damage
to internal organs.

KEYWORDS

for searching the Internet and other reference sources

Kala azar

Parasitic infections

Sand fly

Travel-related illnesses

What Is Leishmaniasis?

The disease occurs when a person becomes infected with any of several
types of
Leishmania
parasites
*
. They spread to people through the bite of female sand flies and can
cause different forms of illness, all of which are called leishmaniasis.
Cutaneous (kyoo-TAY-nee-us) leishmaniasis affects the skin; mucocutaneous
(myoo-ko-kyoo-TAY-nee-us) leishmaniasis attacks the mucous membranes
*
in the mouth, nose, and throat; and visceral (VIH-suh-rul) leishmaniasis
(also known as systemic leishmaniasis or kala azar) damages internal
organs, such as the liver
*
and spleen
*
.

*
parasites
(PAIR-uh-sites) are organisms such as protozoa (one-celled animals),
worms, or insects that must live on or inside a human or other organism
to survive. An animal or plant harboring a parasite is called its host.
Parasites live at the expense of the host and may cause illness.

*
mucous membranes
are the moist linings of the mouth, nose, eyes, and throat.

*
liver
is a large organ located beneath the ribs on the right side of the
body. The liver performs numerous digestive and chemical functions
essential for health.

Cutaneous and mucocutaneous infections can lead to severe scarring and
permanent disfigurement. In patients with a mucocutaneous infection, the
disease can destroy soft tissue in the mouth and nose, drastically
deforming the face. The visceral form of the disease is considered the
most dangerous. It can grow worse over time and is usually fatal if not
treated. Leishmaniasis damages the immune system so that it cannot fight
off infections; these infections are generally the cause of death, not
leishmaniasis itself. In some countries, visceral disease has been found
with increasing frequency in people who also have human immunodeficiency
virus
*
infection.

How Common Is the Disease?

The infection is most common in tropical and subtropical regions, such as
countries in South America, Africa, and Asia, and the number of areas
where it occurs continues to grow. The U.S. Centers for Disease Control
and Prevention (CDC) estimates that one and a half million people around
the world contract cutaneous leishmaniasis each year and half a million
people experience the more serious visceral form of the disease. Ninety
percent of the visceral cases are found in just five countries: India,
Nepal, Bangladesh, Sudan, and Brazil. Leishmaniasis is exceptionally rare
in the United States, although a few cutaneous cases have been diagnosed
in rural southern Texas.

Is It Contagious?

People cannot get leishmaniasis directly from other people. Instead, the
disease spreads through the bite of blood-sucking sand flies. A fly bites
an infected animal or person and takes in the parasite with its meal of
blood. The
Leishmania
parasites reproduce in the fly, which can spread them when it bites
another person. Sand flies are quite small—about a third of the
size of a mosquito—and fly silently, so people often do not even
know the flies are nearby. Less often, the disease can be transmitted
through contaminated blood in a transfusion
*
, by sharing or reusing needles for injecting drugs, or from a mother to
her baby during pregnancy or birth.

What Are the Signs and Symptoms
of Leishmaniasis?

Cutaneous leishmaniasis is marked by sores that often look like volcanoes:
they have a central pit and a raised rim. They can be painful or painless
and may be covered by scabs. The sores tend to appear on the face, arms,
and legs, and some people have as many as 200 of them. Patients with
cutaneous leishmaniasis also may have swollen lymph nodes
*
near the sores. In mucocutaneous cases, the lesions appear in the mouth,
nose, and throat and gradually destroy the soft tissues in those areas.

*
spleen
is an organ in the upper left part of the abdomen that stores and
filters blood. As part of the immune system, the spleen also plays a
role in fighting infection.

*
platelets
(PLATE-lets) are tiny, disk-shaped particles within the blood that play
an important role in clotting.

The visceral form of the disease can cause lack of appetite, serious
weight loss, fever (which can last from 2 weeks to 2 months), and
increasing weakness. It also can lead to an enlarged spleen and liver and
sometimes swollen lymph nodes. Blood tests may show that the patient has
low levels of white blood cells, red blood cells, or platelets
*
. As the disease progresses, the skin can become dark and dry—a
symptom that gave the disease the name kala azar (meaning "black
fever"). In children, visceral leishmaniasis often begins suddenly,
with fever, diarrhea, and cough.

Cutaneous leishmaniasis affects the skin, causing sores that may look
like volcanoes: they have a central pit and a raised rim. The disease
can destroy tissue and lead to permanent scarring.

AP/Wide World Photos

How Do Doctors Make the Diagnosis?

A key to making the diagnosis is learning whether the patient has traveled
to a country where leishmaniasis occurs. During the physical examination,
the doctor also checks the patient's body for the types of sores
seen with the infection. The doctor may take blood samples and tissue
samples from any sores that are found. These samples will be cultured
*
, examined for signs of the parasite, or tested for antibodies
*
to the parasite. For suspected cases of visceral infection, biopsies
*
of the abnormal tissue may be done.

What Is the Treatment?

Doctors treat the infection with prescription medications; many of these
medicines contain antimony
*
. Cutaneous cases usually can be treated at home, but visceral disease may
require hospitalization and supportive care, such as intravenous
*
fluids. Patients who have severe disfigurement from cutaneous, and
especially mucocutaneous, leishmaniasis often need reconstructive surgery
to regain a normal appearance. However, such extensive (and expensive)
treatment is not available to vast numbers of people in developing
countries who contract this disease.

*
cultured
(KUL-churd) means subjected to a test in which a sample of fluid or
tissue from the body is placed in a dish containing material that
supports the growth of certain organisms. Over time, ranging from hours
to weeks, the organisms will grow and can be identified.

*
antibodies
(AN-tih-bah-deez) are protein molecules produced by the body's
immune system to help fight specific infections caused by
microorganisms, such as bacteria and viruses.

*
biopsies
(BI-op-seez) are tests in which a small sample of skin or other body
tissue is removed and examined for signs of disease.

*
antimony
(AN-tih-mo-nee) is an element that has properties of both metals and
nonmetals and can kill or inhibit the growth of certain bacteria.

How Long Does the Disease Last?

Although some cases of cutaneous leishmaniasis clear up on their own, most
cases of mucocutaneous and visceral infection will not get better without
treatment. Left untreated, visceral disease typically leads to death
within 2 years. Cutaneous cases may take several months to heal, even with
treatment, and may return after the treatment has been completed.

What Are the Complications of Leishmaniasis?

The cutaneous and mucocutaneous forms of leishmaniasis often cause
widespread scarring. In mucocutaneous cases, destruction of tissue in the
mouth and nose can lead to facial deformity. Visceral disease can damage
the immune system to the point that it is unable to fight off other
infections. Some patients may need to have the spleen removed if it is
trapping and destroying too many of the person's blood cells, and
advanced cases of disease often result in death.

Can the Disease Be Prevented?

Avoiding sand fly bites is the best way to limit the spread of
leishmaniasis. In areas where the flies live, people are advised to stay
inside from dusk until dawn, when the insects are most active. Wearing
long-sleeved shirts, long pants, and socks and tucking pants into socks
can reduce the amount of bare skin that is vulnerable to fly bites. Using
insect repellent, staying in screened-in or air-conditioned areas,
sleeping under mosquito netting, and spraying living areas with an
insecticide to kill flies also can help lessen the risk of being bitten.

*
intravenous
(in-tra-VEE-nus) means within or through a vein. For example,
medications, fluid. or other substances can be given through a needle or
soft tube inserted through the skin's surface directly into a
vein.

Resources

Organizations

U.S. Centers for Disease Control and Prevention (CDC), 1600 Clifton
Road, Atlanta, GA 30333. The CDC provides a fact sheet and other
information on leishmaniasis at its website.
Telephone 800-311-3435
http://www.cdc.gov

World Health Organization (WHO), Avenue Appia 20, 1211 Geneva 27,
Switzerland. WHO tracks disease outbreaks around the world and offers
information about leishmaniasis at its website.
Telephone 011-41-22-791-2111
http://www.who.int

User Contributions:

I have the cutaneous leishmaniasis for about six months now. I contacted it on a military deployment to Iraq. The Army has yet to do an official biopsy to determine 100% that it is indeed leishmaniasis, although unofficially we know it is. Is there any chance that cutaneous can turn visceral or am I in the clear on that aspect? I ask because these doctors have not had no experience with this before and I want to make sure that I am being treated properly.

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